This invention relates to a transferring method and apparatus for loading and unloading an article to be processed such as a semiconductor wafer to and from a processing position inside a processing chamber defined in a processing vessel, and a high-pressure processing apparatus provided with the transferring apparatus.
In the case of loading and unloading a plate-shaped article to be processed such as a semiconductor wafer into and from a processing apparatus for applying a high-pressure processing or the like, a means for quickly, securely and stably carrying the article while protecting it is necessary. Apparatuses, for example, disclosed in Japanese Registered Utility Model No. 2503732, Japanese Unexamined Patent Publication No. H11-186360 and Japanese Patent No. 3107310 are known as such an apparatus.
In the apparatus disclosed in Japanese Registered Utility Model No. 2503732, a semiconductor substrate or an article to be processed is carried to various processing units or processing apparatuses by a second carrying mechanism after being unloaded from a cassette by a first substrate carrying mechanism and transferred from the first substrate carrying mechanism to the second carrying mechanism or, conversely, processed articles are returned to the cassette from the various processing apparatuses by the first and second substrate carrying mechanisms.
In this apparatus, the second substrate carrying mechanism which transfers the article to and from various processing apparatuses has such a construction as to support the article from below. Similar to this, in the apparatuses disclosed in Japanese Unexamined Patent Publication No. H11-186360 and Japanese Patent No. 3107310, parts thereof that serve to transfer the article to and from the processing apparatuses have such a construction as to support the article from below.
With such apparatuses in which the articles are directly transferred to the processing apparatuses and a portion of the carrying mechanism supports the article from below, the processing apparatuses need to be formed with a clearance through which the article supporting portion enters and exits from the processing apparatuses in order to avoid the interference of the processing apparatuses and the carrier device.
Particularly in the case that this carrying mechanism moves over a relatively long distance, the article supporting portion of the carrying mechanism is obliged to be solid and large since the articles need to be supported with a sufficient strength during carriage. Accordingly, the clearances for allowing the entrance and exit of the article supporting portion into and from the processing apparatuses tend to be enlarged as much.
Such an enlargement of the clearance leads to the enlargement of the processing chamber as a whole defined in the processing apparatus. Various other problems arise in the case that the processing apparatus applies a high-pressure processing. For example, the enlargement of the clearance leads to a longer time required to compress a processing gas and an increase in the amount of the processing gas used, resulting in a reduction in throughput.
Japanese Patent No. 3174691 shows a carrying mechanism which transfers a substrate between a substrate carrier device and a substrate processing apparatus. However, this carrying mechanism is always placed inside a processing chamber. Consequently, the processing chamber is required to have an increased space to accommodate the carrying mechanism.